Across Myanmar, opposition leader Aung San Suu Kyi is stepping up her campaign to change the Constitution by staging street rallies in crowded cities and dusty villages that draw thousand-strong crowds.

She has also begun to broaden her message by challenging the role of the powerful military, which has the clout to veto any charter changes.

At a rally in Lewe town, Naypyidaw, on Sunday, Suu Kyi told a huge crowd: "We are not attacking the military, whose duty is to protect the country and people. When the military was established, it regarded the people as parents.

"I am just urging the military not to take the role it shouldn't take because I want it to be loved by the people."

The twin messages of Suu Kyi's public campaign are closely related.

Her real goal is to change Article 59F of the charter, which bars her from the presidency because of her marriage to a British academic and her two sons' British citizenship.

But to do that, she has to first succeed in amending Article 436, which states that the support of more than 75 per cent of lawmakers is needed for any charter change.

This effectively gives the military, which holds 25 per cent of seats in the national Parliament, a veto on any constitutional amendments.

But the Nobel laureate's move to mobilise the public on this issue is facing a growing pushback from the Tatmadaw, as the Myanmar army is officially known.

The Union Election Commission (UEC), chaired by retired army general Tin Aye, recently reminded Suu Kyi that she swore an oath to the Constitution and so she should not criticise it.

In a letter on May 22, the commission told Suu Kyi that she had made illegal and unconstitutional comments in saying the military should not be afraid of constitutional change in support of democratic reform.

It also warned that her comments could jeopardise the re-registration of her party, the National League for Democracy (NLD), ahead of by-elections later this year and a general election at the end of next year.

The NLD responded tersely by saying that the UEC's caution was inappropriate, and challenged its authority to decide on constitutional matters.

NLD spokesman Nyan Win told The Straits Times in a phone interview on Thursday that the party is not intimidating the army, and is instead aiming to give the military "a chance to be good in Parliament".

Some analysts are sceptical of Suu Kyi's high-pressure public tactics.

Former political prisoner Khin Zaw Win wrote in an e-mail that the street rallies were intended as a "short cut to power on the shoulders of a gullible public".

Aside from the huge rallies, the NLD and activists from the "88 Generation" pro-democracy movement have collected more than 380,000 signatures in Yangon alone demanding a change to Article 436.

Dr Khin Zaw Win, who is based in Yangon, also pointed out that a committee has already been set up to review thousands of proposals to change the Constitution.

"Since a proper process is already under way, strong public pressure is perhaps uncalled for," he said.

There is also the likelihood that Suu Kyi's tactics could backfire, warned Yangon-based analyst Richard Horsey.

He wrote in an e-mail: "Directly and publicly challenging the army may not be a very effective strategy in achieving her objective of changing the Constitution.

"The army is more likely to use its veto over constitutional change if it feels backed into a corner. Mobilising the population can put pressure on (the) government, but it is the army's support that is necessary if the Constitution is to be changed."

Other analysts argue that Suu Kyi has little choice but to raise the temperature in her public campaign.

Phil Robertson, Human Rights Watch's deputy director for Asia, said: "She has to play a more gutsy game, otherwise she will end up (as) just a hood ornament on the transition to democracy. The military will just give the illusion of change."